mjb/altos/ao_flight.c, branch telebt

Use autotools, move altos to src subdir

2009-06-04T17:41:34+00:00

Signed-off-by: Keith Packard

Eliminate RDF tone generation.

2009-05-29T06:17:33+00:00

Now that we have a viable telemetry-signal based RDF device via TeleDongle, there's no reason to continue to waste power and bandwidth with a NFM tone. Signed-off-by: Keith Packard

Avoid 16-bit overflow in velocity computation.

2009-05-24T04:16:22+00:00

Adding two 16 bit integers together can wrap around to negative numbers, this resulted in velocity values which never decreased, making the switch from coast to apogee state not occur. Signed-off-by: Keith Packard

While on the pad, zero out velocity every second

2009-05-18T05:24:53+00:00

We integrate acceleration to get velocity, but that means sitting on the pad for a long time can add substantial error to the velocity value. Each second, take the velocity value from a full second ago and subtract that out of the current velocity. Once we detect boost, this will stop, which means that as long as we detect boost within a second, we won't have subtracted out any "real" velocity. This keeps the pad velocity hovering around zero, which is pretty useful. Signed-off-by: Keith Packard

Abandon use of accelerometer for apogee detect.

2009-05-17T03:04:31+00:00

Integrating the accelerometer data to compute velocity worked for one rocket flight, but additional testing shows that it doesn't work in other airframes. Until we figure out how this should work, we'll rely on the altimeter to detect apogee. Signed-off-by: Keith Packard

Accelerometer-based velocity values are invalid after apogee

2009-05-13T18:00:43+00:00

Because the orientation of the flight computer relative to the ground is unknown after apogee, the accelerometer data cannot be integrated to compute velocity. Main deploy is now based purely on barometric altitude and landing detection no longer checks for a low velocity value. Signed-off-by: Keith Packard

Add velocity check for boost detect via accelerometer

2009-05-13T17:59:04+00:00

Bumping the rocket can cause a brief period of high acceleration, which may cause a mistaken boost detection. Require both a high acceleration and reasonable velocity to trigger boost phase. Signed-off-by: Keith Packard

Don't re-initialize the landing range data at each apogee detect sample

2009-05-11T06:01:16+00:00

The landing range values are used only after apogee detect, so we need only initialize them on the transition from apogee to drogue. Signed-off-by: Keith Packard

Initialize ao_min_vel with |ao_flight_vel|

2009-05-11T06:00:06+00:00

As ao_min_vel is stored as an absolute value, it's important to preserve that invariant, even though we don't expect ao_flight_vel to be negative at coast. Signed-off-by: Keith Packard

Decrease telemetry rate on the pad to 1/sec instead of 20/sec

2009-05-11T05:58:31+00:00

Transmitting telemetry through the radio consumes a significant amount of battery; reducing the rate to 1/sec will reduce power usage while waiting for launch. Signed-off-by: Keith Packard